The present invention relates generally to work tables for power tools and the like, and is more particularly directed to a combination workpiece positioning/hold-down and anti-kickback device for a work table.
A work table for a woodworking device, such as a power saw, router and the like, generally includes a horizontal tabletop on which the workpiece is supported and a fence secured to the tabletop and extending in the direction of movement of the workpiece. The workpiece is moved on the upper surface of the tabletop and is guided along the fence, during a cutting or other woodworking action.
Featherboard and other devices are known for pressing the workpiece against the fence during such movement, and various hold-down devices are known for pressing the upper surface of the workpiece to hold the workpiece down on the tabletop. These devices have some of the following desirable features.
One such desirable feature is the ability to prevent kick-back of the workpiece during a woodworking operation. Another desirable feature is the adjustment of the positioning or hold-down member in lengthwise, transverse and vertical directions relative to the workpiece. Still another desirable feature is the ability to variably adjust the biasing force of the positioning or hold-down member against the workpiece. The applicant is not aware, however, of any devices that include all of these features in a simple arrangement.
Accordingly, it is an object of the present invention to provide a combination workpiece positioning/hold-down and anti-kickback device that overcomes inherent disadvantages of know workpiece positioning/hold-down devices.
It is another object of the present invention to provide a combination workpiece positioning/hold-down and anti-kickback device that presses the side and/or top surface of the workpiece, while preventing kick-back thereof.
It is still another object of the present invention to provide a combination workpiece positioning/hold-down and anti-kickback device in which the positioning or hold-down member is adjustable in lengthwise, transverse and vertical directions relative to the workpiece.
It is yet another object of the present invention to provide a combination workpiece positioning/hold-down and anti-kickback device in which the biasing force of the positioning or hold-down member against the workpiece is variably adjustable.
In accordance with one form of the present invention, a combination workpiece positioning and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a positioning member having a main body, and an arcuate cam surface at one edge of the main body for engaging a side surface of a workpiece on the work table; an adjustment device for moving the positioning member relative to the workpiece, the adjustment device including a lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the positioning member in the lengthwise direction, and a transverse adjustment assembly movable in a direction transverse to the lengthwise direction for adjusting the position of the positioning member in the transverse direction, the transverse adjustment assembly being movably connected to the lengthwise adjustment assembly; a lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a transverse releasable locking device for releasably locking the transverse adjustment assembly relative to the work table at a desired location in the transverse direction; a pivot which pivotally mounts the positioning member to the adjustment device for pivoting movement; a spring connected between the positioning member and the adjustment device for biasing the positioning member with a biasing force in a first pivot direction about the pivot such that the arcuate cam surface is biased in a direction opposite to a feed direction of the workpiece and into engagement with the side surface of the workpiece; and a variable tensioning device for variably adjusting the biasing force of the spring, wherein the lengthwise adjustment assembly includes at least first and second lengthwise adjustment members, the first lengthwise adjustment member being received within an interior portion of the second lengthwise adjustment member.
In accordance with another form of the present invention, a combination workpiece positioning and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a positioning member having a main body, and an arcuate cam surface at one edge of the main body for engaging a side surface of a workpiece on the work table; an adjustment device for moving the positioning member relative to the workpiece, the adjustment device including a lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the positioning member in said lengthwise direction, and a transverse adjustment assembly movable in a direction transverse to said lengthwise direction for adjusting the position of the positioning member in the transverse direction, the transverse adjustment assembly being movably connected to the lengthwise adjustment assembly; a lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a transverse releasable locking device for releasably locking the transverse adjustment assembly relative to the work table at a desired location in the transverse direction; a pivot which pivotally mounts the positioning member to the adjustment device for pivoting movement; a spring connected between the positioning member and the adjustment device for biasing the positioning member with a biasing force in a first pivot direction about said pivot such that said arcuate cam surface is biased in a direction opposite to a feed direction of said workpiece and into engagement with the side surface of the workpiece; and a variable tensioning device for variably adjusting the biasing force of the spring, wherein the lengthwise adjustment assembly includes a lengthwise adjustment member operatively engaged within a guide track of the work table.
In accordance with another form of the present invention, a combination workpiece hold-down and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a hold-down member having a main body, and an arcuate cam surface at one edge of the main body for engaging an upper surface of a workpiece on the work table; an adjustment device for moving the hold-down member relative to the workpiece, the adjustment device including a lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the hold-down member in the lengthwise direction, and a vertical adjustment assembly movable in a vertical direction transverse to the lengthwise direction for adjusting the position of the hold-down member in the vertical direction, the vertical adjustment assembly being movably connected to the lengthwise adjustment assembly; a lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a vertical releasable locking device for releasably locking the vertical adjustment assembly relative to the work table at a desired location in the vertical direction; a pivot which pivotally mounts the hold-down member to the adjustment device for pivoting movement; a spring connected between the hold-down member and the adjustment device for biasing the hold-down member with a biasing force in a first pivot direction about the pivot such that the arcuate cam surface is biased in a direction opposite to a feed direction of the workpiece and into engagement with the upper surface of the workpiece; and a variable tensioning device for variably adjusting the biasing force of the spring, wherein said vertical adjustment assembly includes a vertical adjustment member operatively coupled to said lengthwise adjustment assembly, said vertical adjustment member including an aperture whose length extends in a direction which is non-parallel with respect to a longitudinal length of the lengthwise adjustment assembly, and a clamping device engaging said vertical adjustment member so as to releasably fix a height of the hold-down member with respect to the work table.
In accordance with another form of the present invention, a combination workpiece positioning, hold-down and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a first positioning member having a main body, and a first arcuate cam surface at one edge of the main body for engaging a side surface of a workpiece on the work table; a first adjustment device for moving the first positioning member relative to the workpiece, the adjustment device including a first lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the positioning member in the lengthwise direction, and a first transverse adjustment assembly movable in a direction transverse to the lengthwise direction for adjusting the position of the positioning member in the transverse direction, the transverse adjustment assembly being movably connected to the lengthwise adjustment assembly; a first lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a first transverse releasable locking device for releasably locking the transverse adjustment assembly relative to the work table at a desired location in the transverse direction; a first pivot which pivotally mounts the positioning member to the adjustment device for pivoting movement; a first spring connected between the positioning member and the adjustment device for biasing the positioning member with a biasing force in a first pivot direction about the pivot such that the arcuate cam surface is biased in a direction opposite to a feed direction of the workpiece into engagement with the side surface of the workpiece; a first variable tensioning device for variably adjusting the biasing force of the spring; a non-rotatable hold-down member having a main body, and a second arcuate cam surface at one edge of the main body for engaging an upper surface of a workpiece on the work table; a second adjustment device for moving the hold-down member relative to the workpiece, the second adjustment device including a second lengthwise adjustment assembly movable in the lengthwise direction for adjusting the position of the hold-down member in the lengthwise direction, and a vertical adjustment assembly movable in a vertical direction transverse to the lengthwise direction for adjusting the position of the hold-down member in the vertical direction, the vertical adjustment assembly being movably connected to the lengthwise adjustment assembly; a second lengthwise releasable locking device for releasably locking the second lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a vertical releasable locking device for releasably locking the vertical adjustment assembly relative to the work table at a desired location in the vertical direction; a second pivot which pivotally mounts the hold-down member to the second adjustment device for pivoting movement; a second spring connected between the hold-down member and the second adjustment device for biasing the hold-down member with a biasing force in a second pivot direction about the second pivot such that the second arcuate cam surface is biased in a direction opposite to the feed direction of the workpiece and into engagement with the upper surface of the workpiece; and a second variable tensioning device for variably adjusting the biasing force of the second spring, wherein the lengthwise adjustment assembly includes at least first and second lengthwise adjustment member, and the first lengthwise adjustment member being received within an interior portion of the second lengthwise adjustment member.
In accordance with another form of the present invention a combination workpiece positioning, hold-down and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a first positioning member having a main body, and a first arcuate cam surface at one edge of the main body for engaging a side surface of a workpiece on the work table; a first adjustment device for moving the first positioning member relative to the workpiece, the adjustment device including a first lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the positioning member in said length-wise direction, and a first transverse adjustment assembly movable in a direction transverse to said lengthwise direction for adjusting the position of the positioning member in the transverse direction, the transverse adjustment assembly being movably connected to the lengthwise adjustment assembly; a first lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a first transverse releasable locking device for releasably locking the transverse adjustment assembly relative to the work table at a desired location in the transverse direction; a first pivot which pivotally mounts the positioning member to the adjustment device for pivoting movement; a first spring connected between the positioning member and the adjustment device for biasing the positioning member with a biasing force in a first pivot direction about said pivot such that said arcuate cam surface is biased in a direction opposite to a feed direction of said workpiece into engagement with the side surface of the workpiece; a first variable tensioning device for variably adjusting the biasing force of the spring; a hold-down member having a main body, and a second arcuate cam surface at one edge of the main body for engaging an upper surface of a workpiece on the work table; a second adjustment device for moving the hold-down member relative to the workpiece, the second adjustment device including a second lengthwise adjustment assembly movable in said lengthwise direction for adjusting the position of the hold-down member in said lengthwise direction, and a vertical adjustment assembly movable in a vertical direction transverse to said lengthwise direction for adjusting the position of the hold-down member in the vertical direction, the vertical adjustment assembly being movably connected to the lengthwise adjustment assembly; a second lengthwise releasable locking device for releasably locking the second lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a vertical releasable locking device for releasably locking the vertical adjustment assembly relative to the work table at a desired location in the vertical direction; a second pivot which pivotally mounts the hold-down member to the second adjustment device for pivoting movement; a second spring connected between the hold-down member and the second adjustment device for biasing the hold-down member with a biasing force in a second pivot direction about said second pivot such that said second arcuate cam surface is biased in a direction opposite to the feed direction of said workpiece and into engagement with the upper surface of the workpiece; and a second variable tensioning device for variably adjusting the biasing force of the second spring, wherein said vertical adjustment assembly includes a vertical adjustment member operatively coupled to said lengthwise adjustment assembly, said vertical adjustment member including an aperture whose length extends in a direction which is non-parallel with respect to a longitudinal length of the second lengthwise adjustment assembly, and a clamping device engaging said vertical adjustment member so as to releasably fix a height of the hold-down member with respect to the work table.
In accordance with another form of the present invention, a combination workpiece positioning, hold-down and anti-kickback device for a work table having a fence against which a workpiece is guided, includes a first positioning member having a main body, and a first arcuate cam surface at one edge of the main body for engaging a side surface of a workpiece on the work table; a first adjustment device for moving the first positioning member relative to the workpiece, the adjustment device including a first lengthwise adjustment assembly movable in a lengthwise direction of movement of the workpiece along the work table for adjusting the position of the positioning member in said length-ise direction, and a first transverse adjustment assembly movable in a direction transverse to said lengthwise direction for adjusting the position of the positioning member in the transverse direction, the transverse adjustment assembly being movably connected to the lengthwise adjustment assembly; a first lengthwise releasable locking device for releasably locking the lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a first transverse releasable locking device for releasably locking the transverse adjustment assembly relative to the work table at a desired location in the transverse direction; a first pivot which pivotally mounts the positioning member to the adjustment device for pivoting movement; a first spring connected between the positioning member and the adjustment device for biasing the positioning member with a biasing force in a first pivot direction about said pivot such that said arcuate cam surface is biased in a direction opposite to a feed direction of said workpiece into engagement with the side surface of the workpiece; a first variable tensioning device for variably adjusting the biasing force of the spring; a hold-down member having a main body, and a second arcuate cam surface at one edge of the main body for engaging an upper surface of a workpiece on the work table; a second adjustment device for moving the hold-down member relative to the workpiece, the second adjustment device including a second lengthwise adjustment assembly movable in said lengthwise direction for adjusting the position of the hold-down member in said lengthwise direction, and a vertical adjustment assembly movable in a vertical direction transverse to said lengthwise direction for adjusting the position of the hold-down member in the vertical direction, the vertical adjustment assembly being movably connected to the lengthwise adjustment assembly; a second lengthwise releasable locking device for releasably locking the second lengthwise adjustment assembly relative to the work table at a desired location in the lengthwise direction; a vertical releasable locking device for releasably locking the vertical adjustment assembly relative to the work table at a desired location in the vertical direction; a second pivot which pivotally mounts the hold-down member to the second adjustment device for pivoting movement; a second spring connected between the hold-down member and the second adjustment device for biasing the hold-down member with a biasing force in a second pivot direction about said second pivot such that said second arcuate cam surface is biased in a direction opposite to the feed direction of said workpiece and into engagement with the upper surface of the workpiece; and a second variable tensioning device for variably adjusting the biasing force of the second spring wherein said first lengthwise adjustment assembly includes a lengthwise adjustment member operatively engaged within a guide track of the work table, wherein said first lengthwise adjustment assembly includes a lengthwise adjustment member operatively engaged within a guide track of the work table.